2006-2007 Subaru Impreza Headlamp Assembly: Halogen vs. HID and Common Failures

Halogen vs. HID/Xenon: A Critical Distinction for 2006-2007 Impreza

The 2006-2007 Subaru Impreza, often called the 'Hawkeye' generation, was available with two different headlight technologies. Understanding which type your car has is the most important step before purchasing a replacement.

• Halogen Headlights: Standard on Impreza, Outback Sport, and WRX models, these are the most common type. They use a simple H7 incandescent bulb for the low beam and a 9005 bulb for the high beam. Halogen systems are simple, with power running directly to the bulb.
• High-Intensity Discharge (HID/Xenon) Headlights: These were equipped on the high-performance WRX STI model. HIDs use a D2S bulb that creates a bright, white-blue light from an electrical arc, similar to a welder. This system is more complex and requires a ballast and an igniter to provide the high voltage needed to start and maintain the arc.

Symptoms of a Failing Headlamp Assembly

Problems with headlights aren't always just a burnt-out bulb. The entire assembly can fail in several ways:

• Moisture or Condensation Inside: If you see fog, water droplets, or a 'fishbowl' of water inside the lens, the assembly's seal has failed. This can be caused by age, tiny cracks in the housing, or blocked ventilation tubes. Persistent moisture will quickly burn out bulbs and corrode reflective surfaces.
• Yellow, Hazy, or Cloudy Lens: The outer polycarbonate lens can become yellow and cloudy from years of UV sun exposure. This significantly reduces light output and can be a safety hazard. While light hazing can be polished, severe internal clouding or micro-cracking requires replacement.
• Dim or Flickering Lights: While often a sign of a failing bulb, if new bulbs don't solve the problem, the issue could be a corroded internal wiring harness or a burnt connector pigtail, which is common with the heat generated by halogen bulbs.
• Physical Damage: Cracks in the lens or back housing from impacts can allow water to enter. Broken mounting tabs will cause the headlight to vibrate, leading to a shaky beam pattern and eventual failure.

Known Issues, Recalls, and Technical Service Bulletins (TSBs)

As of mid-2026, there are no specific recalls or Technical Service Bulletins (TSBs) issued by Subaru or the NHTSA for the headlamp assemblies on 2006-2007 Impreza models. The numerous recalls for this vehicle pertain to Takata airbag inflators and potential corrosion of the front lower control arms. The most common owner-reported issues are lens hazing and moisture entry due to aging seals, which are considered normal wear and tear rather than a manufacturing defect.

Buying a Used 2006-2007 Impreza Headlamp Assembly: What to Inspect

A used OEM headlamp is often a better choice than a cheap aftermarket part due to superior optics and fitment. However, careful inspection is key.

1. Verify Halogen vs. HID: First, confirm you are buying the correct type for your car. An STI HID assembly will have a large square hole for the D2S bulb and ballast, while a Halogen assembly will have a smaller round hole for the H7 bulb.
2. Inspect All Mounting Tabs: This is the most critical inspection point. These plastic tabs are brittle and often break during removal or in minor bumps. Check every single tab for cracks or signs of repair. A headlight with broken tabs will not mount securely.
3. Check the Lens Condition: Look for deep scratches, rock chips, and 'crazing' (a network of fine cracks). Minor external yellowing can be fixed with a restoration kit, but deep damage cannot.
4. Look for Signs of Moisture: Check the bottom corners inside the lens for water stains or a white, chalky residue. This indicates the light has had a leak in the past, and the seal is likely compromised.
5. Examine the Seal: Inspect the channel where the lens meets the back housing. Look for signs of it being pried open or resealed with excessive silicone, which suggests a previous moisture problem. A clean, factory seal is best.
6. Check Wiring and Connectors: Ensure the main connector plug and any internal wiring are free of corrosion or heat damage. The plastic around the bulb socket should not be melted or brittle.

Replacement Overview and Headlight Aiming

Replacing the headlamp assembly is a feasible DIY project for those with basic tools.

Basic Steps:

1. Open the hood and remove the plastic clips holding the front grille.
2. Carefully pull the grille straight out to release the bottom clips.
3. Remove the two 10mm bolts on the top of the headlamp assembly.
4. Loosen the push clips on the fender side of the bumper cover to allow it to flex.
5. Reach inside the bumper opening to access and remove the third, 'hidden' 10mm bolt holding a white bracket.
6. Carefully pull the assembly forward and disconnect the main electrical connector.
7. Installation is the reverse of removal. Test the lights before fully reassembling the grille and bumper clips.

Headlight Aiming After Installation

After replacing a headlamp assembly, you must aim the new light to ensure proper visibility and avoid blinding other drivers. The adjustment screws are on the back of the housing.

General Procedure:

1. Park the car on a level surface, 25 feet away from a flat wall or garage door.
2. Turn on the low beams.
3. The top of the light beam's cutoff line should be slightly below the height of the center of the headlight bulb itself.
4. Use an 8mm socket or Phillips screwdriver on the adjustment screws on the back of the housing to move the beam up/down and left/right until it is properly aligned.

Cost Comparison

Part Number Cross-Reference

These part numbers are for the common Halogen assemblies. Always verify the part number on your existing assembly before ordering.

Frequently Asked Questions (FAQ)